In addition to nicotine, cigarette smoke (tobacco) contains MAOIs. MAOIs were commonly prescribed as antidepressants and antipsychotics back in the 50s and 60s, but fell out of favor for various reasons, despite showing far greater efficacy than SSRIs.

(one of these reasons was dietary: MAOIs have bad interactions with the amino acid "Tyramine", found in aged foods. However, Tyramine content in food has dropped dramatically since the 70s, and this is no longer a significant concern)

When I hear “80% of population X exhibits characteristic A”, my first reflex is to guess on whether I think the size of population X is on the order of magnitude of the presence of characteristic X in the general population. If not, I suspect I am learning something more about pop X than char A.

I’d guess there’s orders of magnitude more smokers than schizophrenics, making it seem unlikely smoking is a primary driver, though I’m sure there’s more to it than that.

I hear 80%+ of all perpetrators of sexual violence engage often with porn, but suspect that if porn drove sexual violence, its rates wouldn’t be decreasing. Most heart attack sufferers drink water within days of their cardiac event. All lottery winners have lottery tickets...

I agree with you science nowadays is mostly junk. On the other hand if we can choose to ignore any study that links X to something bad, then this is a conversation not worth having.

Myself I like to err on the side of caution, since my country has free healthcare which means I have to pay for the mistakes of others, so I don't want them making mistakes in the first place. They should feel free to smoke all the weed they want and become psychotic drones in the fucking Congo

That sounds true but is really not - it's just a way to throw out everything because you don't have a counter.